本研究欲開發一壓電製程平台，並利用該平台進行微型麥克風設計、分析與製作。市售商用電容式麥克風由於受到設計上諸多限制，而使得麥克風之訊雜比無法進一步提升，壓電式麥克風則受壓電材料成長品質與蝕刻困難，使得壓電式麥克風發展受限。本研究透過相較簡單的SOI (Silicon-on-insulator wafer) 製程，提出利用結構設計方式增加壓電麥克風之感測靈敏度，利用黃光微影定義出壓電膜層凸塊形狀，縮小感測電極面積，使得主體振膜與壓電膜層之間的應力分布進一步提升，可增加單一壓電麥克風之感測靈敏度，透過有限元素模擬軟體結果顯示，所設計壓電式麥克風，相較傳統設計可提升兩倍感測靈敏度，透過麥克風頻率響應量測結果，初步驗證了利用壓電材料設計微型麥克風的可行性。

This study proposes a sensitivity improving approach for MEMS piezoelectric microphones by using structral design. Compared to exsited commercial microphone constrained by several design limitations, piezoelectric microphones have great potential to achieve higher Signal-to-Noise Ratio. In application, the present design has been implemented on the Silicon-on-Insulator (SOI) wafer. By patterning piezoelectric material, stress distribution in bimorph structure can be improved. Through design different geometry, the sensitivity of piezoelectric microphone can be enhanced 190% from simulation. Reference type microphone design has been measured, and the results can verify the possibility of using piezoelectric platform to fulfill microphone design.

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